The present invention relates to a reservoir for storing articles which is deteriorated by an action of oxygen such as perishable foods, and more particularly to a means for suppressing the deterioration of the articles accommodated in the reservoir by adjusting an oxygen concentration inside the reservoir.
Freshness of perishable foods such as meat is reduced by oxidation. And, majority of bacteria grow under an oxygen atmosphere and thus rot or spoil the foods. On the other hand, some garments and ornaments are discolored by oxidation.
The prior art technology will be described below by taking the foods as an example of the articles which are deteriorated by the action of oxygen.
Conventionally, low temperature reservoirs such as refrigerators or freezers have widely been used in order to suppress possible spoiling or rotting of the foods and to keep their freshness. These low temperature reservoirs need a cooling or freezing system, and thus the reservoirs inevitably have to be large scale. In addition, the running cost is high since the cooling or freezing system is large in power consumption.
Incidentally, an atmospheric gas-adjusted reservoir is partly used as the reservoir especially for professional use. In the atmospheric gas-adjusted reservoir, an atmosphere in a chamber for storage is substituted by an inert gas such as carbon dioxide (See, for instance, "Freshness maintenance of vegetables and fruits appeared in the literatures" (Takeo Shiina, edited by DISTRIBUTION SYSTEMS RESEARCH CENTER CO., LTD. Tokyo JAPAN (1990)).
The atmospheric gas-adjusted reservoir employs a gas cylinder to supply carbon dioxide. Therefore, the reservoir requires a troublesome exchange of gas cylinder.
There is also proposed a means for supplying carbon dioxide which generates carbon dioxide by a combustion of fuel. However, this means requires a troublesome supply of fuel.
The primary object of the present invention is to solve the above-mentioned problems and to provide a reservoir capable of storing articles with a simple equipment.